Asteroid headed towards Earth
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With just 73 days left in 2020, NASA has published an alert that not one, but five asteroids are passing by Earth today, as the agency's Osiris-Rex spacecraft prepares to touch down on a space rock 200 million miles away.

The first three of the day's five space rocks have mercifully passed the Earth by without incident, according to the Asteroid Watch Widget that tracks asteroids and comets that will make relatively close approaches to our planet.

2020 TJ6, measuring 10m in diameter or roughly half a bowling lane, passed the planet at a blistering speed of 40,824kph, but at a safe distance of 1.2 million km. The asteroid was followed by 2020 UX, the tiniest out of the five, which passed the Earth at 190,000km, and 2020 TD6, with a diameter of 7.4m or half the height of the Hollywood Sign.

Still to come are the 14-meter 2020 UK, with a diameter roughly the length of a semitrailer, which is expected to fly past at 6.2 million km.

Bringing up the rear will be the fastest space rock of the day, the one-meter-wide 2020 TF6, which will shoot by at a speed of 43,200kph, just 153,000km away - well within the range of the Moon which orbits the Earth at an average of 385,000km.

None of these compare with humanity's own extreme close flyby expected to take place on Tuesday at the Bennu asteroid located over 200 million miles from Earth on that day.

NASA's OSIRIS-REx will make its first attempt at collecting a sample of the space rock shortly before 2pm ET on Tuesday. The craft is expected to touch down for just a few seconds, long enough for its robotic arm to blast the surface with high pressure gas and vacuum up some of the asteroid's space dust for analysis back here on Earth.

"We're cautiously optimistic that this will be the only time we touch the surface," said Richard Burns, the OSIRIS-REx project manager at NASA's Goddard Flight Center.